Fix equality of contexts to respect alpha-equivalence. Modify dependent elimination packages to reuse the unification result of finding the instance when fetching the eliminator.
Fix equality of contexts to respect alpha-equivalence.
Modify dependent elimination packages to reuse the unification result of finding the instance
when fetching the eliminator.

mattam82/Coq-Equations,mattam82/Coq-Equations,clarus/Coq-Equations